Systems and methods for cathodic protection of an oil and gas well system

ABSTRACT

System, assemblies, and methods for cathodic protection of one or more components of an oil and gas well may include an anode comprising an anodic coating on a surface of at least one first component of the oil and gas well. A cathode may comprise at least one second component of the oil and gas well, where the anode is configured to at least partially inhibit corrosion of the cathode.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of U.S.Provisional Patent Application Ser. No. 63/175,233, titled “SYSTEMS ANDMETHODS FOR CATHODIC PROTECTION OF AN OIL PUMPING SYSTEM,” filed Apr.15, 2021, the disclosure of which is hereby incorporated by thisreference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates, according to some embodiments, tosystems and methods of cathodic protection of an oil and gas well system(e.g., a pumping system) using an anodic coating.

BACKGROUND

Sucker rod pumping systems are commonly used artificial lifting systemsfor oil wells. Suckers rods can be used to implement a rotary or linearreciprocating motion that provides mechanical energy to lift oil frombottom-hole to surface for further processing and refinement.

However, many downhole components including sucker rods, tubing andpumps are made of carbon steel that readily corrodes when introduced tooil compositions containing water and corrosive agents (e.g., acids,oxidizers, bases) including H₂S, CO₂, O₂, and chlorides. Corrosion ofdownhole components lead to pitting that may lead to fatigue andcorrosion cracking of components that is formed at the base of acorrosion pit. This fatigue can be somewhat exacerbated by the cyclicloading nature of sucker rod-driven artificial lifting where cracksoften initiate at high stress points on the sucker rod and can lead to areduction in the rod cross-section to the point where the rod cannotcarry the load and fails. Further, as many oil well systems age and useup the readily available oil deposits, operators must dig deeper to findmore oil. Since the deeper oil reserves tend to contain hotter and morecorrosive (e.g., acids, oxidizers, bases) fluids, digging deeper leadsto even more corrosion on the downhole components causing sucker rodpumping system component failure. Also as wells age and production ratesdecrease, operators often use enhanced recovery methods such as waterand steam flooding, or cyclic steam injection to help boost production.Unfortunately, these methods also introduce large amounts of H₂O whichincreases corrosion.

Some known corrosion mitigation techniques involve the use of chemicalcorrosion inhibitors. While these inhibitors may have someeffectiveness, they are often difficult to transport to the sites ofcorrosion and can often be incompatible with other downhole pumpcomponents such as elastomeric parts. Another strategy involves the useof metal alloys that are inherently more corrosion resistant thangeneral carbon steel components. However, these alloys are generally notcost effective as their production cost outweighs their oftenincremental performance benefit.

A third method of protecting sucker rods includes coating the suckerrods with polymeric coatings that are protective against corrosiveagents. These include thermoplastic polymer coatings (e.g.,polyethylene) and thermosetting fusion bonded epoxy (FBE) coatings. Thethermoplastic polymer coating technique does not bond well with thesucker rod surface and is prone to disbondment. This leads to alimitation of the depth of well in which this coated coiled rod stringcan be installed. The deeper the well, the more squeeze pressure theinjector units, which deploy and retrieve coiled sucker rod strings fromwells, need to hold onto the sucker rod strings. Since the thermoplasticpolymer coating does not bond well enough, the squeeze pressure stripsor sloughs off the polymer coating from the sucker rod surface. This isespecially true when trying to retrieve the coated sucker rod stringfrom the well after it has been down hole for any period of time. Oncethe thermoplastic polymer coating strips or sloughs off, the sucker rodmetal is left unprotected and will begin to corrode. Additionally,thermoplastic polymer coating that has fallen off can plug flow lines.If the coating peels while in the well bore, the loose coating can plugthe pump and/or the flow lines, leading to unwanted and expensiverepairs.

Fusion bonded epoxy coatings provide a modest protection againstcorrosion caused by contact with down well chemicals, but such coatingsare also subject to abrasion. Additionally, application of fusion bondedepoxy coating systems involves complicated, timely, and costlyprocedures. As these coatings are worn, corrosion protection is lost andrepairs to such systems are problematic and expensive.

Another downfall of known sucker rod corrosion protection methods isthat they generally protect only the sucker rods and leave otherdownhole components prone to corrosion and degradation. Therefore,systems and methods are needed that not only protect the sucker rods,but that also protect other system components against corrosive agents.Additionally, systems and methods are needed that are operable toprotect downhole components even after both physical wear and corrosionhas occurred on the sucker rods.

SUMMARY

In some aspects, the techniques described herein relate to a sucker rodpumping system for cathodic protection of components, the systemincluding: an anode including an anodic coating on a surface of a bodyof a sucker rod string including one or more sucker rods; and a cathodeincluding one or more of: a tubing string including a cylinder andconfigured to concentrically contain the sucker rod string, a polishedrod, and a pump; the polished rod configured to be connected to apolished rod clamp above ground and to be connected to a top end of thesucker rod string contained below the ground; or the pump mechanicallyconnected to a bottom end of the sucker rod string, wherein the anode isconfigured to at least partially inhibit corrosion of the cathode.

In some aspects, the techniques described herein relate to a method forcathodic protection using the sucker rod pumping systems discussed inthis section.

In some aspects, the techniques described herein relate to a system forcathodic protection of one or more components of an oil and gas well,the system including: an anode including an anodic coating on a surfaceof at least one first component of the oil and gas well; a cathodeincluding at least one second component of the oil and gas well that isconnected to and configured to be positioned in a location that isuphole or downhole from the at least one first component; and at leastone electrically conductive connection line electrically coupling the atleast one first component and the at least one second component, whereinthe anode is configured to at least partially inhibit corrosion of thecathode.

In some aspects, the techniques described herein relate to a method forcathodic protection of components of a sucker rod pumping system, themethod including: applying an anodic coating on a surface of at leastone first component of the oil and gas well to form an anode component;electrically connecting, via a conductive connection, the anodecomponent to a cathode component including at least one second componentof the oil and gas well; and at least partially inhibiting corrosion ofthe cathode component with the anode component.

Features from any of the disclosed embodiments may be used incombination with one another, without limitation. In addition, otherfeatures and advantages of the present disclosure will become apparentto those of ordinary skill in the art through consideration of thefollowing detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate several embodiments of the present disclosure,wherein identical reference numerals refer to identical or similarelements or features in different views or embodiments shown in thedrawings.

FIG. 1 is an elevational view of a pumping system according toembodiments of the disclosure.

FIG. 2 is an elevational view of a pumping system according toembodiments of the disclosure.

FIG. 3 illustrates a cross-sectional view of a coating on at least onecomponent of an oil and gas well according to embodiments of thedisclosure.

FIG. 4 illustrates a cross-sectional view of a coating on at least onecomponent of an oil and gas well according to embodiments of thedisclosure.

DETAILED DESCRIPTION

As used herein, relational terms, such as “first,” “second,” “top,”“bottom,” etc., are generally used for clarity and convenience inunderstanding the disclosure and accompanying drawings and do notconnote or depend on any specific preference, orientation, or order,except where the context clearly indicates otherwise.

As used herein, the term “and/or” means and includes any and allcombinations of one or more of the associated listed items.

As used herein, the terms “vertical,” “upper,” “lower,” and “lateral”refer to the orientations as depicted in the figures. Further, when usedherein in reference to a location in, or relative to, a wellbore, theterms “above,” “upper,” and “uphole” mean and include a relativeposition proximate the surface of the well, whereas the terms “below,”“lower” and “downhole” mean and include a relative position distal thesurface of the well.

The term “surface” may indicate the surface of the Earth on which aportion of pumping assembly for a well is positioned where the well orborehole extending through and below the surface.

The present disclosure relates to the application of an anodic coating(e.g., metal anodic coating) on a portion of either a coiled orconventional sucker rod that synergistically provides for a cathodicprotection against corrosion for downhole and above-well components of asucker rod pumping system. The anodic coating (e.g., aluminum, zinc,and/or magnesium) may act as a sacrificial anode that will corrode inplace of sucker rod pumping system components acting as a cathode,thereby protecting the cathodic components from corrosion. Each of thesucker rod pumping system components may be electrically connected in acontinuous circuit so that the corrosion protection provided to thesucker rod by the anodic coating will also provide similar protection toall other system components.

In some embodiments, in addition to providing corrosion protection tothe sucker rod, an anodic coating may improve (e.g., decrease) thecoefficient of friction by up to 25% in comparison to the underlyingmetal alone, where the metal alone would exhibit a coefficient offriction that is greater than the coefficient of friction of the anodiccoating. The relatively more soft, ductile, and malleable anodic coatingmay provide surfaces having a relatively lower coefficient of friction,more desirable wear, and self-healing characteristics as is discussedbelow.

Besides providing corrosive protection for down-well components,embodiments of the disclosed anodic coated sucker rods mayadvantageously exhibit self-healing properties in response to wear. Aspreviously described, wear ruins the polymeric protective barriers ofpreviously known systems by causing the barriers to slough off inchunks, thereby exposing the underlying metals. Instead of being removedin chunks, the disclosed anodic coating wears in small portions, whichthen self-heals through a smearing action of the coating to cover thesucker rod portions that were exposed through wear. Additionally, evenwhen localized damage to portions of the anodic coating occurs,corrosion protection of system components is not disrupted since theanodic coating contacts the entire sucker rod string so that theelectrical circuit created through galvanic coupling of the cathode andanode is not disrupted. For example, full cathodic protection may beprovided by a system where from 30% to 40% of the anodic coating hasbeen worn off.

Application of an anodic coating on a coiled or conventional sucker rodas is presented herein includes coating a portion of an entirety ofsucker rod. For example, a sucker rod may have a surface that is about0.1% coated with the anodic coating, or about 5% coated, or about 10%coated, or about 15% coated, or about 20% coated, or about 25% coated,about 30% coated, or about 35% coated, or about 40% coated, or about 45%coated, about 50% coated, or about 55% coated, or about 60% coated, orabout 65% coated, or about 70% coated, or about 75% coated, or about 80%coated, or about 85% coated, or about 90% coated, or about 95% coated,or about 100% coated, where about includes plus or minus 2.5%. A coatingmay include any geometric design. A coating may be applied on a suckerrod as a longitudinal strip and as multiple longitudinal strips. Forexample, a coating may be applied on a sucker rod as two longitudinalstrips that are diametrically opposed to each other. A coating may beapplied circumferentially around a sucker rod. For example, a coatingmay be applied at one or more circumferential strips around a suckerrod. In some embodiments, coated sucker rods and non-coated sucker rodsare connected in an alternative series along a sucker rod string.

A self-healing capability of disclosed cathodic protection methods andsystems is in part driven by an inclusion of anodic coatings containingsoft metals including aluminum, zinc, magnesium, and/or alloys thereof.Soft metal anodic coating compositions smear in the presence of heat andfriction to recoat exposed sucker rod surfaces. Additionally, anodiccoating made of relatively soft metals (e.g., aluminum) may wear awayinstead of spalling off in larger pieces or splinters as do conventionalpolymeric coatings (e.g., FBE and thermoplastic polymer coatings).Therefore, anodic coatings used herein will not generally plug up flowlines or contaminate production fluids. Additionally, anodic coatingsaccording to embodiments disclosed herein do not tend to as readilyspall off of the sucker rod surfaces while being serviced as compared toeither fusion bonded epoxy or thermoplastic polymer coatings.

In some embodiments, a cathodic protection system disclosed herein mayinclude a sealant on a portion of an anodic coating. For example, asucker rod may include an anodic coating on a surface of the sucker rodand a sealant on a surface of the anodic coating. A sealant may beorganic, inorganic, or a mixture thereof. An organic sealant may includean epoxy, a silicone, and a phenol resin. A sealant may include amoisture cured urethane, a urethane, a clear single component moisturecured urethane, a clear two components (2k) aliphatic polyurethane, andcombinations thereof.

A sealant may advantageously fill the porosity of the anodic coating andmay provide physical wear protection of the anodic coating. In someembodiments, a sealant may negate a portion of a cathodic protectionprovided by an anodic coating until it is worn off of the anodiccoating. A sealant may be applied to all or only a portion of the anodiccoating contained on a surface of the sucker rod. For example, a suckerrod may have a surface of the anodic coating that is 0.1% sealed with asealant, or about 5% sealed, or about 10% sealed, or about 15% sealed,or about 20% sealed, or about 25% sealed, about 30% sealed, or about 35%sealed, or about 40% sealed, or about 45% sealed, about 50% sealed, orabout 55% sealed, or about 60% sealed, or about 65% sealed, or about 70%sealed, or about 75% sealed, or about 80% sealed, or about 85% sealed,or about 90% sealed, or about 95% sealed, or about 100% sealed, whereabout includes plus or minus 2.5%.

Disclosed in the present application are methods and systems forcathodic protection of a pumping system (e.g., a sucker rod pumpingsystem for an oil and gas well). As shown in FIG. 1, a sucker rodpumping system 100 includes an anode and a cathode. For example, asdiscussed below, existing components of the system 100 may be used asthe anode and/or the cathode, such that these components perform theirtraditional functions while providing or benefiting from addedprotective features (e.g., corrosion protection) provided by existingcomponent of the sucker rod pumping system 100. By way of example, andas discussed below, an anode may be provided with an anodic coating onone or more components of the sucker rod pumping system 100. Forexample, a surface of a body of a sucker rod string 115 that has one ormore sucker rods may have the anodic coating 101 applied thereto (e.g.,the anodic coating 101 applied on one or more of the sucker rods of thesucker rod string 115). In additional embodiments, other components ofthe sucker rod pumping system 100 may function as the anode and mayinclude the anodic coating 101.

The system 100 may include on or more components (e.g., positioneduphole or downhole relative to the anode) that may be cathodes,including, for example, a progressive cavity (PC) pump 125, a tubingstring 105, a sucker rod string 115, a polished rod 120, a casing head180, a tubing head 170, a composite pumping tee (CPT) 110, a surfacecasing vent line 190, a flow line 140, a flow tee 150, a tubing hanger160, a polished rod clamp 130, and a surface drive unit 135. Inadditional embodiments, other components of the sucker rod pumpingsystem 100 may function as the cathode.

In some embodiments, and as discussed above, the components acting asthe anode and cathode may be electrically connected to one another. Suchelectrical connection may be an electrically conductive connection linethat connects the components. As a depicted example in FIG. 1, asimplified connection line 145 is shown extending between the sucker rodstring 115 and the progressive cavity pump 125. The simplifiedconnection line 145 may be internal to, external to, and/or integralwith the components acting as the anode and cathode and any interveningcomponents.

By way of example, in use, a positive charge may be applied to anodiccoating 101 such that at least a portion of the sucker rod string 115(e.g., or other selected components) acts as an anode. An oppositecharge may be applied to another component or components that areselected as one or more cathodes to be protected (e.g., the progressivecavity pump 125 or other selected components). For example, a negativecharge may be applied to the progressive cavity pump 125 such that atleast a portion of the progressive cavity pump 125 acts as a cathode.

A sucker rod rotary pumping system 100 includes a string of tubing 105containing cylinder and is configured to concentrically contain a suckerrod string 115, a polished rod 120, and a PC pump 125. A system 100 mayinclude a production casing 185 that is located below ground thatincludes a cylindrical interior cavity that is configured to surroundthe tubing 105 in a cylindrical manner (e.g., cylindrically surround ina lateral or radially direction). A production casing 185 may have acasing head 180 at the top of the production casing 185. A casing head180 may mechanically connect a production casing 185 to a tubing headassembly 170. Additionally, a casing head 180 may include a surfacecasing vent line 190 that is mechanically connected to the casing head180 and extends from the casing head and end above ground. The surfacecasing vent line 190 permits gas migration from below ground to thesurface. Each of a tubing string 105, a sucker rod string 115, apolished rod 120, a production casing 185, a casing head 180, a tubinghead assembly 170, and a surface casing vent line 190 may be a cathodethat is protected from corrosion through inclusion of an anodic coatingsurface on a body of a sucker rod string 115.

As shown in FIG. 1, a sucker rod pumping system 100 may include apolished rod 120 that connects to a polished rod clamp 130 both locatedabove ground. The bottom of the polished rod 120 may mechanicallyconnect to a top end of a sucker rod string 115. A polished rod 120 maypartially protrude above ground from a center of a tubing head assembly170 and may be partially housed below ground within the interior cavityof the production casing 185. The bottom end of the sucker rod string115 may mechanically connect to a top end of a progressive cavity pump125 that is located towards the bottom of the production casing 185. Insome embodiments, a progressive cavity pump 125 or plunger pump may beswitched out for an electric submersible pump (ESP) artificial liftsystem.

The system 100 may include a sucker rod string 115 containing one ormore sucker rods. Each sucker rod in the sucker rod string 115 includesa first threaded end, a second threaded end, a solid cylinder, and ananodic coating 101 on a surface of a body of the sucker rod. Applicationof the anodic coating 101 onto a sucker rod or coiled sucker rod string115 surface includes a surface preparation and blasting step and athermal anodic coating spray step. The thermal anodic coating spray stepmay involve a process where melted or heated anodic coating is sprayedonto the sucker rod surface. An anodic coating 101 may be applied ontoan outside surface of the sucker rod individually or onto a coiledsucker rod string 115. The anodic coating 101 may be applied as thin as0.20 millimeter (0.008 in.) as thick as 0.51 millimeters (0.020 in.), orit may be applied to other thicknesses according to design needs.

In some embodiments, the anodic coating 101 may comprise a suitableelectrically conductive material, such as, for example, a metallic,semi-metallic, and/or graphitic material. For example, the anodiccoating 101 may include, without limitation, copper, tungsten carbide,cobalt, aluminum, magnesium, zinc, iron, platinum, palladium, niobium,graphite, graphene, nichrome, gold, silver, alloys thereof, any suitablemetallic material, and/or any other suitable electrically conductivematerial, without limitation.

The sucker rod pumping system 100 may include other components such as asurface drive unit 135 attached to a tubing head 170 through a compositepumping tee 110. A tubing head 170 may be mechanically connected to atubing hanger 160. A tubing hanger may include one or more flow lines140 that may transfer produced oil from the well to any form of knownoil collection vessel or oil transport system. A flow line 140 mayconnect to a composite pumping tee 110 through a flow tee 150.

The present disclosure relates to methods of cathodic protection ofdownhole components of a sucker rod pumping system 100. A methodincludes a step of producing oil using a sucker rod pumping system 100including an anode and a cathode as described herein where the anodeprotects the cathode from corrosion.

In some embodiments, as is shown in FIG. 2, a pumping system includes areciprocating sucker rod pumping system 200 including an anodic coatingon a surface of a body of a sucker rod string 115. A system 200 includesa prime mover 205 mechanically connected to a beam pumping unit 210including a horsehead 215. The prime mover 205 provides mechanicalenergy to the beam pumping unit 210 and the horsehead 215, whichtranslates into a reciprocating motion for down well components throughthe polished rod 120. The horsehead 215 may be mechanically connected tothe polished rod 120 through a carrier bar 220. The polished rod 120 ispartially contained above the surface as well as below the surface andtransitions through a wellhead 225, which caps the top of the well.System 200 includes a surface casing 230 that concentrically contains agas flow 235, an oil flow 240, an intermediate casing 245, a productioncasing 185, a production tubing 105, and a sucker rod string 115. Asshown in FIG. 2, an intermediate casing 245 goes deeper into the groundthan the surface casing 230 and concentrically contains a productioncasing 185. The production casing 185 concentrically contains the suckerrod string 115, a tubing anchor 250, a pump 255 and ends at perforations260 that may provide effective flow communication between the system 200and the oil reservoir.

A reciprocating rod system 200, as shown in FIG. 2 may include a suckerrod or sucker rod string 115 containing an anodic coating that mayprovide cathodic protection to one or more of a polished rod 120, awellhead 225, a surface casing 230, an intermediate casing 245, aproduction casing 185, a production tubing 105, a tubing anchor 250, anda pump 255. In some embodiments, a system includes a cathode includingthe polished rod 120, the wellhead 225, the surface casing 230, theintermediate casing 245, the production casing 185, the productiontubing 105, the tubing anchor 250, and the pump 255.

The corrosion and wear associated with downhole systems reduces thelifespan of sucker rod pump systems. Embodiments of disclosed systemsand methods for cathodic protection of sucker rod pump systems mayrelatively increase the lifespan of and therefore reduces operatingcosts of using the sucker rod pump systems to produce oil from an oilwell.

As is shown in Table 1 below, a disclosed anodic coating outperformscomparative thermosetting fusion bonded epoxy (FBE) and polyethylenecoatings. Even when using a thinner anodic coating (e.g., 10-20 mils),it provides for both barrier and cathodic protection whereas FBE andpolyethylene coatings only provide barrier protection. Anodic coatingsare generally impermeable to fluids whereas FBE and polyethylenecoatings are semi-permeable. Being impermeable to fluids advantageouslyminimizes or prevents fluid ingress between the coating and the suckerrod metal substrate since entrapped fluid may corrode the metalsubstrate and lead to a detachment of the coating from the surface ofthe metal substrate. Anodic coatings as disclosed herein may havevirtually or substantially no limit to clamping pressure of the rodinjector used to either deploy or retrieve a coiled sucker rod, whereasFBE and polyethylene coatings both have limitations. Additionally,anodic coatings generally have no depth or handling equipmentlimitations whereas FBE and polyethylene coatings both do. As is shownin Table 1, the response to mechanical damage of an anodic coating is tosmear, whereas FBE gouges off and polyethylene coatings peel off. Anodiccoatings have excellent adhesion, whereas FBE has good and polyethylenecoatings have fair. Additionally, anodic coatings require no specialcoating disposal. Also, anodic coated sucker rods may operate attemperatures of over 200 ° C. where FBE is limited to about 90° C.

TABLE 1 Comparison of Anodic Coatings to FBE and Polyethylene CoatingAnodic Polyethylene Property coating FBE Coating Thickness (mils) 10-2020-30 125-250 Corrosion resistance Form of protection Cathodic BarrierBarrier and barrier Permeable No Yes Yes Serviceability Clampingpressure No limit Limited Limited Depth limitation None Yes Yes Handlingequipment None Yes Yes Response to Smear Gouge Peel mechanical damageAdhesion Excellent Good Fair Disposal of Standard N/A Specialrod/coating Operating +200° C. ~90° C. <90° C. temperature

FIG. 3 illustrates a cross-sectional view of a coating on at least onecomponent of an oil and gas well (e.g., sucker rod 300). As shown inFIG. 3, the coating 302 may be applied about a circumference of thesucker rod 300 (e.g., an entire circumference).

As also depicted in an idealized schematic form, a conductive element304 may couple the sucker rod 300 to another component 306 of the oiland gas well. As above, the conductive element 304 may be internal to,external to, and/or integral with the sucker rod 300 and the anothercomponent 306 acting as the anode and cathode, respectively, and anyintervening components.

FIG. 4 illustrates a cross-sectional view of a coating on at least onecomponent of an oil and gas well (e.g., sucker rod 400). As shown inFIG. 4, the coating 402 may be applied at selected locations about acircumference of the sucker rod 400. For example, as discussed above,the coating 402 may applied as one or more longitudinal strips 404extending along a length of the sucker rod 400 (e.g., along alongitudinal axis of the sucker rod 400). In some embodiments, thecoating 402 may be applied on sucker rod 400 as two or more longitudinalstrips 404 (e.g., two, three, four, or more) that are positioned onopposing about the sucker rod 400.

As also depicted in an idealized schematic form, a conductive element406 may couple the sucker rod 400 to another component 408 of the oiland gas well. As above, the conductive element 406 may be internal to,external to, and/or integral with the sucker rod 400 and the anothercomponent 408 acting as the anode and cathode, respectively, and anyintervening components.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments are contemplated. The various aspects andembodiments disclosed herein are for purposes of illustration and arenot intended to be limiting.

Terms of degree (e.g., “about,” “substantially,” “generally,” etc.)indicate structurally or functionally insignificant variations. In anexample, when the term of degree is included with a term indicatingquantity, the term of degree is interpreted to mean±10%, ±5%, or +2% ofthe term indicating quantity. In an example, when the term of degree isused to modify a shape, the term of degree indicates that the shapebeing modified by the term of degree has the appearance of the disclosedshape. For instance, the term of degree may be used to indicate that theshape may have rounded corners instead of sharp corners, curved edgesinstead of straight edges, one or more protrusions extending therefrom,is oblong, is the same as the disclosed shape, etc.

What is claimed is:
 1. A sucker rod pumping system for cathodicprotection of components, the system comprising: an anode comprising ananodic coating on a surface of a body of a sucker rod string comprisingone or more sucker rods; and a cathode comprising one or more of: atubing string comprising a cylinder and configured to concentricallycontain the sucker rod string, a polished rod, and a pump; the polishedrod configured to be connected to a polished rod clamp above ground andto be connected to a top end of the sucker rod string contained belowthe ground; or the pump mechanically connected to a bottom end of thesucker rod string, wherein the anode is configured to at least partiallyinhibit corrosion of the cathode.
 2. The sucker rod pumping system ofclaim 1, wherein each sucker rod of the sucker rod string furthercomprises: a first threaded end and a second threaded end; and a bodyexhibiting a substantially cylindrical shape.
 3. The sucker rod pumpingsystem of claim 1, wherein the anodic coating comprises at least one ofaluminum, magnesium, zinc, or an alloy of aluminum, magnesium, or zinc.4. The sucker rod pumping system of claim 1, wherein the cathode furthercomprises a production casing configured to be located below the ground,the production casing comprising a cylindrical interior cavityconfigured to cylindrically contain the tubing string, the polished rod,at least a portion of the sucker rod string, and the pump.
 5. The suckerrod pumping system of claim 4, wherein the cathode further comprises acasing head and a tubing head assembly, the tubing head assemblyconfigured to be located partially above the ground and mechanicallyconnected to the production casing through the casing head.
 6. Thesucker rod pumping system of claim 5, wherein the polished rod isconfigured to partially protrude above the ground from a center of thetubing head assembly and to be partially housed below the ground withinthe cylindrical interior cavity of the production casing.
 7. The suckerrod pumping system of claim 5, wherein the cathode further comprises asurface casing vent line mechanically connected to the casing head, thesurface casing vent line configured to extend from the casing head andto end above the ground.
 8. The sucker rod pumping system of claim 1,wherein only a portion of the surface of the body of the sucker rodstring is coated with the anodic coating.
 9. The sucker rod pumpingsystem of claim 8, wherein the anodic coating is applied incircumferential strips around the body of the sucker rod string.
 10. Thesucker rod pumping system of claim 1, wherein the anode furthercomprises a sealant on at least a portion of the body of the sucker rodstring.
 11. A method for cathodic protection of components of a suckerrod pumping system, the method comprising producing oil using the suckerrod pumping system of claim
 1. 12. A system for cathodic protection ofone or more components of an oil and gas well, the system comprising: ananode comprising an anodic coating on a surface of at least one firstcomponent of the oil and gas well; a cathode comprising at least onesecond component of the oil and gas well that is connected to andconfigured to be positioned in a location that is uphole or downholefrom the at least one first component; and at least one electricallyconductive connection line electrically coupling the at least one firstcomponent and the at least one second component, wherein the anode isconfigured to at least partially inhibit corrosion of the cathode. 13.The system for cathodic protection of claim 12, wherein the cathode andthe anode comprise portions of a downhole artificial lift system. 14.The system for cathodic protection of claim 13, wherein the anodecomprises at least a portion of a rod string of the downhole artificiallift system.
 15. The system for cathodic protection of claim 13, whereinthe cathode comprises at least one of a tubing string, a polished rod, apump, a sucker rod string, a casing head, a tubing head, a compositepumping tee, a casing vent line, a flow line, a flow tee, a tubinghanger, a polished rod clamp, or a surface drive unit.
 16. A method forcathodic protection of components of a sucker rod pumping system, themethod comprising: applying an anodic coating on a surface of at leastone first component of the oil and gas well to form an anode component;electrically connecting, via a conductive connection, the anodecomponent to a cathode component comprising at least one secondcomponent of the oil and gas well; and at least partially inhibitingcorrosion of the cathode component with the anode component.
 17. Themethod of claim 16, further comprising forming the cathode component andthe anode component with existing components of a downhole artificiallift system, each of the cathode component and the anode componentconfigured to perform another function related to the oil and gas well.18. The method of claim 17, further comprising forming the cathodecomponent with at least one of a tubing string, a polished rod, a pump,a sucker rod string, a casing head, a tubing head, a composite pumpingtee, a casing vent line, a flow line, a flow tee, a tubing hanger, apolished rod clamp, or a surface drive unit.
 19. The method of claim 16,further comprising applying a sealant to a portion of the anodecomponent.
 20. The method of claim 16, further comprising applying theanodic coating to only a portion of a rod string of a downholeartificial lift system.